Python/data_structures/Graph/FloydWarshall.py

49 lines
1.1 KiB
Python
Raw Normal View History

from __future__ import print_function
2017-10-13 06:02:05 +00:00
def printDist(dist, V):
print("\nThe shortest path matrix using Floyd Warshall algorithm\n")
for i in range(V):
for j in range(V):
if dist[i][j] != float('inf') :
print(int(dist[i][j]),end = "\t")
else:
print("INF",end="\t")
print()
2017-10-13 06:02:05 +00:00
def FloydWarshall(graph, V):
dist=[[float('inf') for i in range(V)] for j in range(V)]
for i in range(V):
for j in range(V):
dist[i][j] = graph[i][j]
for k in range(V):
for i in range(V):
for j in range(V):
if dist[i][k]!=float('inf') and dist[k][j]!=float('inf') and dist[i][k]+dist[k][j] < dist[i][j]:
dist[i][j] = dist[i][k] + dist[k][j]
printDist(dist, V)
#MAIN
V = int(input("Enter number of vertices: "))
E = int(input("Enter number of edges: "))
2017-10-13 06:02:05 +00:00
graph = [[float('inf') for i in range(V)] for j in range(V)]
for i in range(V):
graph[i][i] = 0.0
2017-10-13 06:02:05 +00:00
for i in range(E):
print("\nEdge ",i+1)
src = int(input("Enter source:"))
dst = int(input("Enter destination:"))
weight = float(input("Enter weight:"))
graph[src][dst] = weight
2017-10-13 06:02:05 +00:00
FloydWarshall(graph, V)